Electric heaters for heating the interior of a motor vehicle are well known and have been in use for many years. For example, a U.S. Pat. No. 4,232,211 of Hill discloses an automobile auxiliary heater to supply heat to the passenger's compartment of an automobile car body. As disclosed, a fan initially draws cold air into a fan chamber of the main inlet cross duct and forces it through an electric heating coil and then through one of two converging branch outlet ducts to a common outlet and at the same time directs the heated air into the passenger compartment. When the compartment has been heated preliminarily, the operator de-energizes the electric heating coil and reverses the fan causing it to direct outside air through the conventional engine radiator-connected liquid heater and then through the opposite converging branch outlet duct. Thus supplying air heated by the conventional heater to the passenger compartment. Electricity for the electric heating coil is provided by the car alternator and/or storage battery.
A more recent U.S. Pat. No. 5,187,349 of Curhan et al. discloses a deep frost and passenger compartment heater system. As disclosed, a system for heating the passenger compartment of an automotive vehicle has a hot water heater receiving heat from a vehicle engine arranged in series with a self-regulating electrical resistance heater of positive temperature coefficient of resistivity that has a power source for energizing the electrical resistance heater. A fan directs air in heat transfer relation to the hot water heater and to the electrical resistance heater in sequence to provide a heated air output to the passenger compartment. Fan speed is controlled to regulate the volume of air directed in heat transfer relation to the heaters so that the electrical resistance heater is promptly and consistently capable of heating the volume of air to at least a selected minimum temperature of 100° F. This provides a passenger compartment with comfort beginning very promptly after engine startup even on a cold day.
Additionally, a U.S. Pat. No. 6,002,105 of Tamada discloses an air conditioning control apparatus for vehicles. As disclosed, a first positive temperature coefficient (PTC) heater and a second PTC heater are provided at the downstream side of a heater core that uses engine cooling water for its heat source, and the second PTC heater is positioned at a foot outlet. Under conditions that require the use of the PTC heaters, power is supplied to all the PTC heaters if the discharge mode is set to a FOOT mode or a DEF/FOOT mode, whereas power is supplied only to the first PTC heater if the discharge mode is set to a DEFROST mode. In an air conditioning control apparatus for vehicles with a heater core and PTC heaters warm air at appropriate temperatures can be supplied through both the foot outlet and the defrost outlet during an initial stage of heating in which the temperature of the engine cooling water is low. In addition, since no power is supplied to the second PTC heater unless the foot outlet is open, energy resources are saved.
Notwithstanding the above, it is presently believed that there is a need and a potential commercial market for an improved heating system in accordance with the present invention. There should be a commercial market for such heaters because they provide a rapid response upon entering the motor vehicle to heat the passenger compartment in cold weather.
Further, it is presently believed that the improved heaters in accordance with the present invention will provide not only rapid response time and can be added to present day heaters with minimum costs and will be reliable over a long period of time. Such heaters are uniquely provided by a plurality of miniature gas igniters.